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Abstract Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a space‐borne instrument dedicated to monitoring high‐energy transients, including Terrestrial Gamma‐ray Flashes (TGFs) and Terrestrial Electron Beams (TEBs). We implemented a TGF/TEB search algorithm for GECAM, with which 147 bright TGFs, 2 typical TEBs and 2 special TEB‐like events are identified during an effective observation time of ∼9 months. We show that, with gamma‐ray and charged particle detectors, GECAM can effectively identify and distinguish TGFs and TEBs, and measure their temporal and spectral properties in detail. A very high TGF‐lightning association rate of ∼80% is obtained between GECAM and GLD360 in east Asia region.

Abstract Drift rate is a very important parameter in the evolution of stock price, which has significant impact on the corresponding option pricing. This paper deals with an inverse problem of recovering the drift function by current market prices of options. Different from the usual inverse volatility problem, our mathematical model does not tend to zero at infinity, which may bring great trouble to theoretical analysis and numerical calculation. To overcome this difficulty, we use an artificial boundary and homogenization technique to transform the original problem into a homogeneous initial boundary value problem on a bounded domain. Then, based on the optimal control framework, we construct the corresponding optimization problem and strictly prove the well-posedness of the minimizer. Finally, we design an iterative algorithm to obtain the numerical solution. We give some typical examples to verify the validity of our method.

Artificial supercavitation is one of the most prospective technique for underwater drag reduction, but it still faces some unsolved roadblocks, like cavity stability, noise, power etc. This article aims at investigating the instability of cavity with the strong jet impingement, and analyzing jet behavior in restricted space. A multiphase model using coupled VOF and level set method is adopted to capture the gas-liquid interface. By changing the position of jet nozzle exit and the jet intensity, a series of numerical simulation is performed. Firstly the transient evolution of the cavity interface under the effect of the high-speed jet is obtained. Numerical model is validated by comparing with the experimental data. Then the criterion to determine the transition between different jet/cavity interaction mechanisms is established based on a non-dimensional distance parameter. Furthermore, the entrainment mechanism inside the cavity is analyzed and provides useful insights on enhancing the cavity stability with strong jets.

Natural rubber (NR) and butyl rubber (IIR) blends were compatibilized by isobutylene-isoprene block copolymer (IIBC) which was specifically synthesized with a relatively high content of isoprene (14.5% mole fraction). Aiming at high damping elastomers, the IIR acts as the high damping phase dispersed in the natural rubber (NR) matrix in this blend. The morphology and microstructure was characterized by atomic force microscope (AFM) and transmission electron microscope (TEM). The results indicated that the IIBC as a compatibilizer could greatly increase the interfacial thickness. Damping property was studied by dynamic mechanical thermal analyzer (DMTA) and rubber processing analyzer (RPA). The results showed that the loss factor greatly increased with adding IIBC, and this may be due to the improved stress transfer promoting the IIR phase to deform and then dissipate energy. The tensile test demonstrated that the tensile strength and modulus increased when 4 parts per hundred rubber [phr] of IIBC was added. Finally, the NR and new NR/IIR isolation bearing samples were prepared and tested on a pressure shear testing machine that could simulate the actual situation during an earthquake.The results showed that hysteretic loss (for one cycle) of the new NR/IIR sample is 83% higher than that of the NR sample, rendering the compatibilized blends potential in isolation rubber bearings application.

Abstract Abyssal manganese nodules have been explored widely for their economic potential and paleoenvironmental significance. Debate about whether biogenic or physical‐chemical processes are responsible for their formation remains because of difficulties in quantifying ancient microbiological contributions. To address this question, we investigated microbial fossils in manganese nodules from the western Pacific Ocean by integrating scanning electron microscope, transmission electron microscope, and synchrotron transmission X‐ray microscope observations. Our results suggest that the nodules host abundant fossil biogenic magnetite and manganese‐oxidizing bacteria. These organisms engage in redox reactions or live in environments with redox gradients. By combining magnetic properties and observations of fossil biogenic magnetite morphology, we estimate magnetofossil abundances and further assess fossil biogenic manganese oxide in nodules. Our results imply that manganese nodule formation appears to be dominated by biomineralization with an additional terrestrial contribution. Extensive biomineralization in ultralow‐productivity oceanic environments suggests that manganese nodule formation is an important aspect of biogeochemical cycling in abyssal seafloor environments.

The original article [1] contains an error in Fig. 5e whereby the immunofluorescence of ΔNp63α in the ME group is incorrectly presented; thus, the corrected figure is shown ahead.

Polystyrene nanospheres have been synthesized by atom transfer radical polymerization (ATRP) to control the molecular weight distribution in the aqueous system. The crucial factor in such a system is the ligand that adjusts the solubility of the catalyst in different phases to control the concentration of both the activator and the deactivator in reaction phase. The effect of different ligands including ethylenediamine, 1,10-phenanthroline (phen) and 4,4-dinonyl-2, 2-bipyridyl (dNbpy) on the catalytic solubility in the organic and aqueous phase has been investigated. The molecular weight distribution of polymer obtained in this way was analyzed by gel permeation chromatography (GPC). It showed that the obtained polymer particles presented a broad molecular weight distribution (polydispersity index 1.78) with ethylenediamine as the ligand, but the polymerization rate was high and conversion reached 96.8%. The molecular weight distribution of polystyrene was narrowest with dNbpy as ligand, but the conversion was lowest and only achieved to 69%. Possible reasons were the influence of the structure of three different ligands on the control of ATRP reaction. SEM and GPC indicated that the polystyrene nanospheres presented regular sphere with a diameter of about 120 nm and uniform molecular weight distribution, which possessed a significant potentials in drug carrier field.

Although patterns between plant diversity and ecosystem productivity have been much studied, a consistent relationship has not yet emerged. Differing patterns between plant diversity and productivity have been observed in response to spatial variability of environmental factors and vegetation composition. In this study, we measured vegetation cover, plant diversity, productivity, soil properties and site characteristics along an environmental gradient (mobile dune, semi-fixed dune, fixed dune, dry meadow, wet meadow and flood plain grasslands) of natural sandy grasslands in semiarid areas of northern China. We used multivariate analysis to examine the relationships between environmental factors, vegetation composition, plant diversity and productivity. We found a positive correlation between plant diversity and productivity. Vegetation composition aggregated by the ordination technique of non-metric multidimensional scaling had also a significantly positive correlation with plant diversity and productivity. Environmental gradients in relation to soil and topography affected the distribution patterns of vegetation composition, species diversity and productivity. However, environmental gradients were a better determinant of vegetation composition and productivity than of plant diversity. Structural equation modeling suggested that environmental factors determine vegetation composition, which in turn independently drives both plant diversity and productivity. Thus, the positive correlation between plant diversity and productivity is indirectly driven by vegetation composition, which is determined by environmental gradients in soil and topography.

Background and Objectives: We know that in low- and middle-income countries maternal and children's under nutriment is responsible for the advancement in deaths and other diseases. A study was designed here to establish a relationship between maternal and children's nutriment in northwestern rural China. Methods: We conducted this prevalence analysis between October 2016 to December 2016 in northwestern rural China by choosing 2021 mothers of children (5 months < age ≤ 24 months) as study subjects. We used standard and calibrated methods and techniques to measure the weight and height of mothers and horizontal lengths of children. Results: We calculated the Z-scores of 'weight for height' (WfH), 'weight for age' (WfA) and 'height for age' (HfA) and found the values less than -2 for 8.2%, 10.5% and 12.6% children, respectively. We found association between nutriment of children and maternal anthropometrical features and also between maternal characteristics and Z-scores of HfA (P = 0.012) and WfH (P = 0.042) of children was also achieved. Conclusion: Maternal good nutriment and good salary is found to be beneficial for children's nutriment. Thus for the betterment of mother and child's health, maternal nutriment as well as her guaranteed financial empowerment should be improved. [ABSTRACT FROM AUTHOR]

Polystyrene nanospheres have been synthesized by atom transfer radical polymerization (ATRP) to control the molecular weight distribution in the aqueous system. The crucial factor in such a system is the ligand that adjusts the solubility of the catalyst in different phases to control the concentration of both the activator and the deactivator in reaction phase. The effect of different ligands including ethylenediamine, 1,10-phenanthroline (phen) and 4,4-dinonyl-2, 2-bipyridyl (dNbpy) on the catalytic solubility in the organic and aqueous phase has been investigated. The molecular weight distribution of polymer obtained in this way was analyzed by gel permeation chromatography (GPC). It showed that the obtained polymer particles presented a broad molecular weight distribution (polydispersity index 1.78) with ethylenediamine as the ligand, but the polymerization rate was high and conversion reached 96.8%. The molecular weight distribution of polystyrene was narrowest with dNbpy as ligand, but the conversion was lowest and only achieved to 69%. Possible reasons were the influence of the structure of three different ligands on the control of ATRP reaction. SEM and GPC indicated that the polystyrene nanospheres presented regular sphere with a diameter of about 120 nm and uniform molecular weight distribution, which possessed a significant potentials in drug carrier field. [ABSTRACT FROM AUTHOR]

The article discusses a study on the density and characteristics of ant mounts at varying dune stabilization stages in order to understand the changes in ant disturbance in the restoration of sandy ecosystems. The study area was located at the southern part of the Horqin Sandy Land of Inner Mongolia, Northern China with a temperate continental semiarid monsoonal climate. It concludes that dune stabilization and the restoration of ground vegetation influences the activities and behavior of ants.

Composites containing Yb-filled CoSb3 and well-distributed Yb2O3 particles are synthesized by in situ reaction method. The structural, chemical, and transport properties of the composites are studied. Some Yb2O3 particles with microsize locate at the grain boundaries of matrix and others distribute within YbyCo4Sb12 grains as nanoscale inclusions. The combination of the “rattling” of Yb ions inside the voids of CoSb3 and the phonon scattering of the oxide defects results in a remarkable reduction in the lattice thermal conductivity. The thermoelectric performance of the composites is significantly improved, and the maximum figures of merit reach 1.3 for the Yb0.25Co4Sb12/Yb2O3 and 1.2 for the Yb0.21Co4Sb12/Yb2O3 composites at 850 K. [ABSTRACT FROM AUTHOR]

Eggshell quality is associated with hatch-ability, and ultrastructural organization is an impor-tant eggshell quality parameter. To the determine the relationship of shell ultrastructural properties with hatchability, we measured the effect of eggshell thick-ness, mammillary layer thickness, and the average size of mammillary cones on hatchability. Eggs with thick shells and thick mammillary layers had the highest in-cidence of hatching. As such, hatchability correlated positively with both eggshell thickness (r = 0.30; P < 0.05) and mammillary layer thickness (r = 0.28; P < 0.05). In addition, the correlation between the aver-age size of mammillary cones and hatchability was not statistically significant. However, a significant positive correlation was observed between the average size of mammillary cones and mammillary layer thickness. It can be concluded that eggshell thickness and mammil-lary layer thickness affect hatchability. [ABSTRACT FROM AUTHOR]